MSK and FSK modulation are both constant-envelope modulation, meaning that the data contained in the signal is not reflected in variations in amplitude. Phase modulation may also be thought of as frequency modulated data, since phase and frequency are related to each other by either an integration operation or a differentiation operation. In fact, it is well known that OQPSK with half-sine pulse shaping is equivalent to MSK modulation. OQPSK with half-sine pulse shaping is the modulation technique called out in the IEEE (Institute for Electrical and Electronics Engineers) 802.15.4 standard, which is an IEEE standard applicable to low power radio networks. It would be beneficial to have a radio that would be 802.15.4 standards compliant as well as consume a very low amount of power when receiving data. To date, all existing radio solutions on the market are high powered devices, typically drawing more than 15 mA. Many commercially available radios draw 30 mA or more. One reason for the high power consumption of many existing 802.15.4 radios is that their receiver demodulators have power hungry blocks such as high-speed analog to digital converters that are used for signal demodulation.